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81.
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Domestication is a process of selection driven by humans, transforming wild progenitors into domesticated crops. The grapevine (Vitis vinifera L.), besides being one of the most extensively cultivated fruit trees in the world, is also a fascinating subject for evolutionary studies. The domestication process started in the Near East and the varieties obtained were successively spread and cultivated in different areas. Whether the domestication occurred only once, or whether successive domestication events occurred independently, is a highly debated mystery. Moreover, introgression events, breeding and intense trade in the Mediterranean basin have followed, in the last thousands of years, obfuscating the genetic relationships. Although a succession of studies has been carried out to explore grapevine origin and different evolution models are proposed, an overview of the topic remains pending. We review here the findings obtained in the main phylogenetic and genomic studies proposed in the last two decades, to clarify the fundamental questions regarding where, when and how many times grapevine domestication took place. Finally, we argue that the realization of the pan-genome of grapes could be a useful resource to discover and track the changes which have occurred in the genomes and to improve our understanding about the domestication. 相似文献
84.
Gabriella Dellino Teresa Laudadio Renato Mari Nicola Mastronardi Carlo Meloni 《国际生产研究杂志》2018,56(4):1458-1485
The paper proposes a decision support system (DSS) for the supply chain of packaged fresh and highly perishable products. The DSS combines a unique tool for sales forecasting with order planning which includes an individual model selection system equipped with ARIMA, ARIMAX and transfer function forecasting model families, the latter two accounting for the impact of prices. Forecasting model parameters are chosen via two alternative tuning algorithms: a two-step statistical analysis, and a sequential parameter optimisation framework for automatic parameter tuning. The DSS selects the model to apply according to user-defined performance criteria. Then, it considers sales forecasting as a proxy of expected demand and uses it as input for a multi-objective optimisation algorithm that defines a set of non-dominated order proposals with respect to outdating, shortage, freshness of products and residual stock. A set of real data and a benchmark – based on the methods already in use – are employed to evaluate the performance of the proposed DSS. The analysis of different configurations shows that the DSS is suitable for the problem under investigation; in particular, the DSS ensures acceptable forecasting errors and proper computational effort, providing order plans with associated satisfactory performances. 相似文献
85.
Enhancement of the Performance of Perovskite Solar Cells,LEDs, and Optical Amplifiers by Anti‐Solvent Additive Deposition
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86.
Michael T. Combs David D. Johnson Gabriella Szekely-Klepser 《Journal of surfactants and detergents》2005,8(3):263-269
The separation and detection properties of various ethoxylated polymers were investigated with atmospheric pressure ionization
liquid chromatography/mass spectrometry (LC/MS). Interesting chromatographic elution behavior based on functionality was noted.
LC/MS using in-source CID (collision-induced dissociation) and tandem mass spectrometry (MS/MS) detection was compared for
end-group identification. Excellent end-group identification was achieved when the end-group molecular weight (MW) was greater
than 100 Da and the average MW of the polymer was less than 400 Da by both MS/MS and in-source CID. In cases where the end-group
MW was less than 100 Da, because of the low mass cut-off in a quadrapole ion trap analyzer, in-source CID produced the only
characteristic end-group ions. The use of a dual scan function allowed investigation of the oligomeric distribution followed
by a narrow low-mass scan using in-source CID to generate end-group information. This approach is applicable on instruments
without MS/MS capability. 相似文献
87.
Gabriella?A.?M.?Falc?o Maria?B.?C.?Vitorino Tatiara?G.?Almeida Marcelo?A.?G.?Bardi Laura?H.?Carvalho Eduardo?L.?CanedoEmail author 《Polymer Bulletin》2017,74(11):4423-4436
Environmental problems caused by the increased waste associated with short-term use of plastic materials, particularly by the food packaging industry, prompted the search for biodegradable alternatives. This contribution studied one of these alternatives, poly(butylene adipate-co-terephthalate)—PBAT, a polymer that is fully biodegradable in common landfills, compounded with a small amount of Cloisite 20A organoclay. Materials were mixed in a laboratory internal mixer and films prepared in a chill roll extruder. Results show that the presence of organoclay does not increase degradation of the polymer matrix during processing, nor affects its crystallization characteristics. However, organoclay addition significantly diminished oxygen and carbon dioxide permeability of the films, making them a very interesting alternative for the food packaging industry. 相似文献
88.
Tuning Sulfur Oxidation States on Thioether‐Bridged Peptide Macrocycles for Modulation of Protein Interactions
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Gabriella T. Perell Rachel Lynn Staebell Mehrdad Hairani Alessandro Cembran Prof. William C. K. Pomerantz 《Chembiochem : a European journal of chemical biology》2017,18(18):1836-1844
Thioethers, sulfoxides, and sulfonium ions, despite diverse physicochemical properties, all engage in noncovalent interactions with proteins. Thioether‐containing macrocycles are also attracting attention as protein–protein interaction (PPI) inhibitors. Here, we used a model PPI between α‐helical mixed lineage leukemia (MLL) protein and kinase‐inducible domain interacting (KIX) domain to evaluate oxidation effects on sulfurcontaining macrocycle structure, stability, and protein affinity. Desolvation effects from various polarity states were evaluated computationally and experimentally at the side chain, amino acid, and peptide level. Sulfur‐containing side chains spanned polarity ranges between all‐hydrocarbon and lactam bridges for modulating solubility, cellular uptake, and affinity. Helical propensity studies showed that, although oxidized sulfur‐containing side chains could be tolerated, conformational effects were sequence‐dependent. In some cases, proteolytic stability, binding capacity with KIX, and increased helicity were obtained as first steps toward developing PPI inhibitors. 相似文献
89.
Ferretti M Andrei S Caldini G Grechi D Mazzali C Galanti E Pellegrini M 《The Science of the total environment》2008,396(2-3):180-192
Prior to 2000 a network of conventional ozone (O3) analysers existed in the Province of Firenze (Tuscany, central Italy). Between 2000 and 2004 the network was extended to incorporate a newly designed bioindicator network of tobacco plants (Nicotiana tabacum Bel W3). The objective was to set-up an integrated monitoring system to obtain estimates of ground-level O3 concentrations over the whole study area (3513 km2) in order to fill data gaps and cover reporting requirements. The existing conventional monitors were purposefully located mainly in urban areas. A total of 45 biomonitoring sites were selected using a systematic design to cover the target area. Two to five additional biomonitoring sites were co-located with conventional O3 analysers for calibration purposes, and five more sites for independent validation of modelled O3 concentrations. Visible Leaf Injury Index (LII) on the tobacco plants was significantly correlated (P: 0.018/0.0014) with a series of O3 exposure variables (mean of weekly 1-hour maxima, M1; mean of 7-hour means, M7; 24-hour mean, M24; and weekly AOT40). LII was found to be a significant predictor of weekly means of the O3 exposure variables with a standard error of estimates between 13.6 and 24.3 microg m(-3) (absolute values). LII was mapped with an ad-hoc spatial model over the study area at a 22 km grid resolution, and mapped values were used to predict O3 concentrations by means of a first order linear model. Results showed that high estimates of O3 (up to 188 microg m(-3) as mean of weekly maxima, M1) occurred more frequently in hilly and mountainous areas, with a spatial pattern changing on an annual basis. Predicted O3 concentrations were not significantly different from the measured concentrations (P: 0.34), although marked differences were observed for individual sites and years. The study provided evidence that integration of monitoring networks using different methods can be a viable option to obtain estimates of O3 concentrations over large areas. 相似文献
90.
Orsolya Kinga Gondor Judit Tajti Kamirn ron Hamow Imre Majlth Gabriella Szalai Tibor Janda Magda Pl 《International journal of molecular sciences》2021,22(21)
Although the relationship between polyamines and photosynthesis has been investigated at several levels, the main aim of this experiment was to test light-intensity-dependent influence of polyamine metabolism with or without exogenous polyamines. First, the effect of the duration of the daily illumination, then the effects of different light intensities (50, 250, and 500 μmol m–2 s–1) on the polyamine metabolism at metabolite and gene expression levels were investigated. In the second experiment, polyamine treatments, namely putrescine, spermidine and spermine, were also applied. The different light quantities induced different changes in the polyamine metabolism. In the leaves, light distinctly induced the putrescine level and reduced the 1,3-diaminopropane content. Leaves and roots responded differently to the polyamine treatments. Polyamines improved photosynthesis under lower light conditions. Exogenous polyamine treatments influenced the polyamine metabolism differently under individual light regimes. The fine-tuning of the synthesis, back-conversion and terminal catabolism could be responsible for the observed different polyamine metabolism-modulating strategies, leading to successful adaptation to different light conditions. 相似文献